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1.
研究了具L^1类(自由项)的非线性椭圆和抛物方程熵解和重正规化解的关系,首先对椭圆型情况,熵解和重正规化解是等价的,对抛物型情况,证明了任一重正规化解一定是熵解。  相似文献   

2.
半空间上一类非线性抛物型方程的衰减性   总被引:1,自引:0,他引:1  
在半空间上讨论了一类非线性抛物型方程弱解的时间衰减性,获得了其解在L^2范数下衰减率为t-n/2(1/r-1/2),其衰减率与线性热传导方程的衰减率相同.  相似文献   

3.
研究了Fredholm和Voltella型线性积分方程快速求解问题,通过在L^2(R^d)空间中构造高维Haar小波基,给出了Fredholm和Voltella型线性积分方程快速求解算法,使得原有算法的复杂度O(mn^d)降为O(mn)。数值算例表明了快速求解高维积分方程数值解是可行的。  相似文献   

4.
讨论了一类非线性Schrodinger方程iut=-Δu-k(x)|u|^4/Nu的初值问题,其中k(x)为RN上的有界可微函数,得到其爆破解在t→T(爆破时间)的几个重要性质:在L^2空间中强极限的不存在性,爆破点以及L^2集中性质.  相似文献   

5.
在奇异初值条件下,研究非线性抛物方程ut-Δu=f(x,u)在权空间L^rδ(x)(Ω)中解的存在性、正则性与唯一性,其中δ(x)是x到边界aΩ的距离.在临界与次临界指数下,其解u∈C([0,T],L^rδ(x)(Ω)),并且在C([0,T],L^rδ(x)(Ω))∩L^∞loc((0,T),L^∞(Ω))意义下唯一.  相似文献   

6.
用Galerkin方法研究了一类一般非线性抛物方程的混合问题,在给定条件下得到了解的存在唯一定理,并在此条件下得出其解在L^2空间连续依赖于初始条件。  相似文献   

7.
研究带位势V(x)∈L^2(R^a)的非线性Schroedinger方程的Cauchy问题的解的存在性,利用Kato—Rellich定理证明Schroedinger算子H=A—V在H^2(R^n)中的自伴性从而由Stone定理得知H=A—V在H^2(R^n)中生成酉群,据此研究了含比F(u)=|u|^2σu更一般的非线性项时方程的解的存在性。  相似文献   

8.
讨论了如下一类带有齐次边界条件的非线性抛物方程ut-△u=|△↑u|^p+α(x)u^q。解的爆破问题,给出了方程解梯度爆破和L^∞爆破的条件.  相似文献   

9.
利用Fourier分解方法讨论一类非线性抛物方程弱解的长时间性态,证明了其解在L^2范数下衰减速率为(1 t)^-n/4。  相似文献   

10.
讨论了一类二阶拟线性Sobolev方程初边值问题的混合体积元方法,给出了在矩形网格剖分下的混合体积元格式,得到了离散解的最优H(div)模和L^2模误差估计.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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